Process of extracting potash salts and other products from silicious rocks.



UN TE amass PATENT canton.

EDWARD: HART, or EASTON, PENNSYLVANIA.

rnocass uE nx'rnac'rme POTASH SALTS Annornnia rnonucrs FROM sILIcIoos nooKs. Y

No Drawing.

Specification of Letters Patent. Patented July 11, flail. Application filed June 13/ 1908. Serial 1%. 435,311.

To all whom it may concern:

Be it known that I, EDWARDHART, a citi= zen of the United States of America, residing at- Easton, in the county of Northampton and State of Pennsylvania, have invented certain new and useful Improvements in Processes of Extracting Potash Salts and other Products from Silicious Rocks, of which the following is a specification.

My invention relates to the manufacture of pot-ash and other products resulting from the decomposition of feldspars andlike rocks,

the object thereof being to provide a simple, eflicient and economical method which can be successfully practiced on any. desired scale. I I The invention consists essentially in the production of potassium salts and other commercially valuable substances by fusing orthoclase with a barium compound and carbon or other reducing agent, said carbon being usually in the form of powdered" anthracite coal.

obtained other than potassium salts so that,

as a result-,- the treatment of potassium bear- .ing rocks for theex'traction of their products is a successful commercial undertaking.

The addition to the silicates insoluble in acids, ,of one molecule of a basic oxid such as lead monoxid or barium monoxid, fol- 40' lowed by fusion, results in the production of a silicate easily decomposed by an acid such as sulfuric, nitric, or muriatic. .VVhen treated with sulfuric acid, for example, we get lead, or barium, sulfate, and sulfate of potassium. Since such rock usually contains also aluminum in quantity, there results alsoalumi'num sulfate. Such a solution containing sul- This solution may also contain sulfates of sodium, magnesium, iron n'iangahese, etc., which may be se arated by methods known to those versed in the art. The great difliculty, however, inthe connnercial utilization of such methods has been ,the high cost of the basic o'xid necessary and the, pro- .duction of large' qaantities of insoluble residue of little or no value. I have succeeded, however, in decomposing potash-feldspar or orthoclas'e in such a manner that all the resulting products become valuable commercially; for I have discovered that, when barium sulfate, barit or barytes (BaSOQ) and carbon, in the orm of powdered anthracite coal for example, aramiized' with powdered feldspar or other insoluble rock containing potassium or aluminum or both,

and the mixture heated to fusion, a lassfifs" obtained; which when powdered is com-- pletely decomposed by mineral acids yieldmg a residue which may be utilized" as a pigment for the manufacture of paints, or for other purposes, and a solution containing the potassium, aluminum, and" other metals in soluble form capable ofsepara tion by methods well known to thoseversed in the art. Or, to describe thep'rocess in greater detail,,when a mixture of barium sulfate, orthoclase and carbon, oi. other reducing material, for-example 233 parts by weight of barium sulfate, 278: parts weight of orthocla'se and 24 parts by weight of carbon or an equivalent amount of other reducing material is heated to fusion, the carbon first reduces the barium sulfate to sulfid. This takes place at a red heat as follows:

The barium sulfid then combines with the orthoclase at a strong red heat, with production ofa potassium aluminum barium silicate and expulslon of the sulfur, only a small portion of ,the latter remaining as barium sulfid dissolvedin the resulting glass. A small portion of the potassium is volatilized but/most' of this condenses in the fines. The necessary maximum tempera-- ture for accomplishing these reactions probably does not exceed 1500 C. When 10' the glass isfinely pulverized and treated with a slight excess of diluted sulfuric acid atfa boiling heat in leaden vessels, the proportions being for example 430 parts by weight of the glass and 310 parts by weight of oil of vitriol, the latter preferably being diluted to about half strength the glass is or colored paint; both the ingredients of this mixture havingbeen found specially useful for this purpose. As an example,-

, when one molecular proportion of orthoclase or potassium aluminum silicate (KAISi O (one of the feldspars), is fusedwith one atomic proportion of barium sulfate and two molecular proportions of powdered car- I bon from anthracite coal a slag or glass is formed which when powdered finely and 40 "insoluble residue consisting of silica (SiO treated with dilute sulfuric acid gives an i: and barium sulfate, which when washed,

dried andgroundwith oil makes an excellent paint; and a solution which when evaporated gives crystals of potassium 4 aluminum alum.

Orthoclase can readily be obtained nearly free fronriron' and'fonthis reason the alum ment then consists entirely of silica.

obtailfed is of greater purity'than that now made frombauxite. I

It is clear that other sulfates besides barium sulfate may be used, but barium sulfate appears to be the best as it gives a pigment entirely insoluble in water as a very finely divided powder. Lead or strontium sulfates might be used but would usually be too expensive and give an inferior pigment. Sodium and potassium sulfates may also be employed but the pig- It is clear that ready formed sulfids such as those of bariunf, strontium, lead and potassium or sodium may also be used, omitting the carbon or other reducing material. It is clear also that other means may be used for decomposing the fused glass than the' one suggested. Thus if hydrochloric acid were used, a mixture ofthe chlorids of potassium, aluminum, and barium, would result, which may be separated by means known to those versed in the art. If nitric acid were used'nitrates would be formed. In both these cases the insolubleresidue would be silica which is valuablecommercially; a

,In case sulfuric acid is used the resulting mixture of barium sulfate and silica when boiled with sodium carbonate would give soluble sodium silicate and sulfate leaving insoluble barium carbonate which may be sold as such or converted into nitrate or chlorid by means of the proper acid.

The furnace to be employed may be of either the blast furnace or the reverberatory type. An electric furnace, orany other suitable kind, may, however, be employed, 1 am not restricted to any particular construction offurnace, and the details thereof may vary widely. The materials when placed in the furnace will commonly be in a crushed state, preferably, though not necessarily, crushed to a size which will pass a sieve having 100 meshes to the inch. The carbon is ordinarily used in the form of pulverized or powdered anthracite coal.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

l. The process of treating insoluble potassium bearing rocks comprising fusing said rock in the presence of barium sulfid, pulverizing the glass thus obtained, treating it with a mineral acid and separating the soluble constituents of the product thus formed from the insoluble constituents tfihereof, substantially as described and specied.

2. The process of treating insoluble p0 tassium bearing rocks comprlsmg fusing scribed and specified.

3. The process-of treating orthoclase feldspar comprising fusing said feldspar in the presence of barium sulfid, thus producing a potassium aluminum barium glass, pulverizing said glass, treating it with sulfuric acid and separating the soluble constituents of the product thus formed including salts containing potassium from the insoluble constituen'ts thereof including silica and barium sulfate, substantially as described and specified. a

4. The process of treating orthoclase feldconstituents of the product thus formed,

spar comprising fusing one molecular proportion thereof with one molecular proportion of barium sulfate and two atomic proportions of powdered carbon, pulverizing the glass thus obtained, treating it with sulfuric acid and separating the soluble i scribed and specified. V I In testimony whereof I aifix my signature in presence of two witnesses. j EDWARD HART. i \Vitnesses i Hnx n' MOKEEN', J I.,

I H. Snnmvooo YOUNG.

including potassium aluminum alum from the insoluble constituents, including s lica Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

' I Washington, D. C.

and barium sulfate, substantially as dein 

